494? GEOLOGICAL REMARKS 



For this purpose, it must be further stated, as a 

 part of the description of the Cartlane Craig, that 

 near the middle of the great fissure, we find the 

 channel of the stream crossed, by a mass of green- 

 stone, or floetz-trap rock, which traverses the 

 strata in a direction almost perpendicular to the 

 course of the hollow at that place. In the neigh- 

 bourhood of the greenstone, smaller ^^eins or por- 

 tions of the same substance may be traced running 

 in a similar direction, and exhibiting at some 

 places the characters of basalt. The immediate 

 connection of these smaller branches or veins 

 with the largest mass, is concealed by the soil and 

 coppice-wood, and debris in the bed of the water ; 

 but in the language of the Huttonian School, 

 they would be described as shooting from it. 



Now, on the principles of the igneous theory, 

 the presence of greenstone in the position which 

 it occupies here, aflfords at once the solution re- 

 quired ; and the Cartlane Craig becomes an 

 example on a large scale, of disruption and dislo- 

 cation produced by a melted or fluid mass, burst- 

 ing upwards from the bowels of the earth. 



On the other hand, the first part of the descrip- 

 tion I have given, clearly resolves this phenome- 

 non into the effect of what is called in the aqueous 

 theory, subsidence, of which it possesses all the 

 data to form a case. Such an explanation, every 

 appearance and circumstance connected with the 



